Compensator for induction motors



H. F. STRATTON COMPENSATOR FOR INDUCTION MOTORS July 3, 1923.

Filed July 26 1922 3 Sheets-Sheet 1 IN V EN TOR.

VI E N m T T A July 3, 1923. 1,460,926

H. F. STRATTQN COMPENSATOR FOR INDUCTION MOTORS Filed July 26 .v 1922 3 Sheets-Sheet 2 INVENTOR.

July 3, 1923. 1,460,926

H, F., STRATTON COMPENSATOR FOR INDUCTION MOTORS Filed July 26 1922 3 Sheets-Sheet 5 Mum IN V EN TOR.

A TTORNEYL.

Patented July 3, 1923.

UNITED STATES PATENT OFFICE.

HARRY I. STBATTON, F CLEVELAND HEIGHTS, OHIO, -.dSSIGrNOB, TO THE ELECTRIC CONTROLLER & MANUFACTURING COMPANY, OF CLEVELAND, OHIO, A CORPORA- rrox or 01110.

' coxrnuss'ron ron rrmucrrou morons.

To all whom it may comem:

Be .it known that I, HARRY F. Srnsrron, a citizen of the United States, residing at Cleveland Heights, inthe county of Cuya hoga and State of Ohio, have invented new and useful Improvements in Compensatols for Induction 'Motors, of which the followin is a specification.

y invention relates to compensators for induction motors. One of the objects there of is to provide a device for the class mentioned, in which the starting contacts are closedby a partial operation of a handle, whereby a series transition magnet with its armature initially biased to closed position is energized, there being revision, upon further movement of the handle, for reversing the bias of the armature so that, when the current in the magnet winding is reduced to a predetermined value, a force stored in a spring by the movement of the handle causes the throw of the contacts to running position, together with means for restoring the contacts to oif-position directly from running position upon the opening of 'the motor circuit or the reduction thereof to and the handle being removed and Fig. 2, v

a front view of the said features with the side of the casing removed. Figs. 3, at and are somewhat diagrammatic views showing the position of the parts of my invention in their oil, starting, and running positions, respectively, and Fig. 6 is a wiring diagram illustratin the operation of the lnvention.

On the rawings, 1 and 2 represent respectively the frontand the rear sides of the casing, and 3 and 4, the right and left ends thereof. 5 is a horizontal shaft or rod supported in the ends 3 and 4 and rovided externall of -the casing with t e handle 6 which is operatively connected to the hub 7 of the lever or arm 8 also carried by the shaft 5.

A metal frame 9 having the end membore 10 and 11 is pivotally supported on the shaft 5 which p through the members between their ends. The lower ends of the members support the bar 12 of wood or other insulating material extending parallel with the shaft 5 and supportin front contacts l3 and rear contacts 14. The upper ends of the members 10 and 11 are connected by the cross-member 15 which has an upwardlyofiset portion 16 arranged to engage the front end or the stop 17 secured to the rear side 2 of the casing. Within the frame 9 is the frame 18 having the end members 19 and 20 carried by the shaft 5, the horizontal member 21 having the offset portion 22 engageable withthe rear stop face 23 on the stop 17. The lower ends of the members 19 and 20 support the bar 24 of insulating material which carries the contact fingers 25 which are engageable with the contacts 13.

To the side 2 of the casing are bolted the two hangers 26 which support at their lower ends the bar 27 of insulating material which carries contacts 28 arranged to be engaged by the contacts 14, only one contact 28 being shown on the bar27 in Fig. 1. Their inclusion in Fig. 2 would confuse the drawing but they are shown in Fig. 6.

he arm 8 carries the armature 29 which engages the poles 30 of the magnet 31 secured to the posts 32 on the end 3 of the casing and having the winding or spool 33, 34 being a shading coil on one of the poles 30. The upper end of the arm 8 carries the spring-supported disk or contact 35 which bridges the contacts 36 carried by the member 37 of the L-shaped device 38 pivotall supported by the pins 39 extending throu ll the end '3 of the casing and through t e member 40 of the device 38, the pins 39 being surrounded by: the spring 41 which yieldingly press the member 40 against the inner face of the end 3. The member 40 carries a push-button 42 projecting through the end 3 for operating the device 38 so as to move the contacts 36 away from the disk or contact 35 to open the circuit ofthe winding 33. v

A toggle having its members 43 and 44 pivoted together on the pivot 45 has the member 43 carried by the pivot 46 in the portion 16 of the frame 9, and the member 44 carried by the pivot 47 on the lug 48 secured to the front side 1 of the casin The side 1 su ports the bracket 49 on whic is mounted t e magnet 50 having for its armature the upiper end of the lever 51 pivoted on the sha or rod 52 whose ends are supported by the ends 3 and 4. The arma ture is provided with the spring 53 which tends to pull the armature away from the magnet 50.

54 is a lever pivoted between its ends on the pin 55 on the end 3 and having its upper end 68 bent toward the end 4 so as to rest upon the armature 51. A s ring 56 stronger than the spring 53 hol s the armature against the magnet 50, despite the action of the spring 53 under conditions to be stated presently.

The member 19 of the frame 18 carries a bracket 57 having the top shoulder 58 and the bottom shoulder 59. A coiled spring 60 rests on the shoulder 59 and engages the un- 63 to hold the frames 9 and 18 in the positions shown on Fi 1 and to store energy for operating the rame 9 after the spring has been compressed upon the 0 eration of the finger 61, as will be explaine presently. The arm 8 has the lug 66 which engages the tail 67 of the lever 54 and rocks the end 68 of the said lever away from the armature 51, thereby leaving the armature under the opening control of the spring 53 and the holding control of the magnet 50. The armature 51 has 9. lug or cam 69, which operates the toggle members 43 and 44 to flex the same when the armature is actuated by the spring 53, as shown in Fig. 5.

An oil tank 70 is hooked to the lower edge of the casing and surrounds the contacts carried by the bars 12, 24 and 27.

The parts on Figs. 3, 4 and 5 have been somewhat modified inshape and position, in order that parts which lie behind other parts on Figs. 1 and 2, may be readily understood as to their operation.

The parts bein initially as in Figs. 1, 2, 3 and 6, the handle 6 is moved toward the front, or from right to left, which, before it reaches its final osition, causes the finger 61 to act throug' the spring 60, which is stronger than the spring 65, to compress the latter and move the frame 18 until the contacts 25 engage the contacts 13, after which the portion 22 of the frame 18 engages the stop face 23 and prevents further movement of the frame 18. As soon as the contacts 13 and 25 meet, the winding of the transition magnet 50 is energized, as shown in Fig. 6, wherebythe magnet attracts the armature 51 with a force stronger than that exerted by the -spring 53 to Bull the armature away from the magnet. pon the closing of the contacts 13 and 25 the supply lines L, L and L are connected to the compensator having the windings 71 and 72, and the motor M is connected to the compensator through taps on the windings 71 and 72 in a manner well known and readily understood from Fig. 6. The motor starts and runs at slow speed.

The handle, when moved still further to its limit, brings the contact 35 into engagement with the contacts 36 whereby a circuit is closed through the no-voltage winding 33 which generates a flux which traverses the poles 30 and the armature 29, and holds the arm 8 in its final position as shown in Figs. 4 and 5 until the current in the winding 33 falls to such a value that the flux generated thereby cannot hold the armature 29 against it, or until the push-button 42 is operated to rock the device 38 and move the contacts 36 away from the contact 35, thereby opening the circuit of the winding 33, as is clear from Fig. 6.

The sad further movement of the handle 6 is permitted by the yielding of the spring under the pressure of the finger 61, and causes the lug 66 by engagement with the finger 67 to rock the biasin lever 54 away from the armature 51, as s own in Fig. 4, thereby leaving the armature under the op posing influences of the s ring 53 and the winding 50. As soon as t e current in the winding 50 drops to a predetermined value due to the acceleration of the motor, the flux from the winding 50 becomes too weak to hold its armature 51 which then under the influence of the spring 53 moves away from the armature, causing the cam 69 to flex the toglgle members 43 and 44, thereby allowing t e compressed spring to operate the frame 9 which moves the contacts 13 away from the contacts 25, and the contacts 14 into engagement with the running contacts 28, the contacts 13 and 14 being connected together as shown in Fig. 6. The parts are now as in Fig. 5 and the motor M is connected directly to the supply lines and ma run at full speed.

pon the operation of the push-button 42 or the decrease of current in the novoltage winding 33, the parts move to the positions shown in Figs. 1 and 3 without the starting contacts 25 being again closed, owing to the action of the spring 65 which causes the frames 9 and 18 to return to-' gether in spaced relation.

The nut 73 turns on the core 74 of the magnet 50 to adjust the core in the magnet to vary the pull of the latter on the armature 51.

I claim 1. In a starting compensator for induction motors, an operating handle, starting contacts engaged upon partial movement of the handle, a magnet energized when the said contacts are closed, an armature therefor, means for biasing the armature to open position but overcome by the magnet only when the current therein is above a predetermined value, a second means stronger than the first biasing means and opposing the same, means 0 rated on further movement of the hand e, for removing the second biasing means after the magnet has been energized, means for storing energy during the operation of the handle, tending to close the running contacts, means for preventing the closing of the running contacts, and means operated by the armature when released from the magnet, for releasing the preventing means, whereby the said stored energiv may close the running contacts.

2. n a starting compensator for induction motors, an operating handle, starting contacts engaged upon partial movement of the handle, a magnet energized when the said contacts are closed, an armature therefor, means for biasing the armature to open position but overcome by the magnet only when the currenttherein is above a predetermined value, a second means stronger than the first biasing means and opposing the same, means operated on further movement of the hand e, for removing the second biasing means after the magnet has been energized, means for storing energy during the operation of the handle tending to close the running contacts, means for preventing the closing of the runningcontacts, means operated by the armature when released from the magnet, for releasing the preventing means, whereby the said stored energy may close the running contacts, and a no-voltage winding for holding the contacts closed.

3. In a starting compensator for inductionmotors, an operating handle, a motor, starting contacts and running contacts therefor,

' means actuated by the handle for closing the starting contacts and for storing energy tending to close the running contacts, means restraining the energy-storm means, an electromagnet having its windmg energized by the motor current, an armature for the electromagnet biased to open position but prevented from opening when the motor current exceeds a predetermined value, and

means controlled by the armature when opening to release the restraining means,

whereby the running contacts may close.

4. In a starting compensator for induction motors, an operating handle, a motor, starting contacts and running contacts therefor, means actuated by the handle for closing the starting contacts and for storing energy tending to close the running contacts, means restraining the ener -storing means, an electromagnet having its winding controlled b the motor current, an-armature for the e ectromagnet biased to open position but prevented from opening when the motor current exceeds a predetermined value, means controlled bv the armature when opening to release thezrestraining means, whereby the running contacts may close, and a no-voltage electromagnet holding the cont acts closed.

5. In a starting compensator for induction motors, an operating handle, a motor, starting contacts and running contacts therefor, means actuated by the handle for closing the starting contacts and for storing energy tending to close the running contacts, means restraining the energy-storing means, an electromagnet having its winding controlled by the motor current, an armature for the electromagnet biased to open position but prevented from opening when the motor current exceeds a predetermined value, means controlled by the armature when opening to release the restraining means, whereby the running contacts may close, a no-voltage electromagnet holding the contacts closed, and a push-button device with contacts in the circuit of the winding of the no-voltage magnet.

6. In a starting compensator for induction motors, an operating handle, a motor, starting contacts and running contacts therefor, means actuated by the handle for closing the starting contacts and for storing energy tending to close the running contacts, means restraining the energy-storing means, an electromagnet having its winding controlled by the motor current, an armature for the elec'tromagnet biased to open position but prevented from opening when the motor current exceeds a predetermined value, means controlled by the armature when opening to release the restraining means, whereby the riinnin contacts may close, and means restraining tie opening of the armature until the magnet winding is energized.

7., in a starting compensator for" induction motors, an operating handle, a motor, starting contacts and running contacts therefor, means actuated by the handle for closing the starting contacts and for storing energy tending to close the running contacts, means restraining the energy-storing means, an electromagnet having its winding controlled by the motor current, an armature for the e ectromagnet biased to open position but prevented from opening when the motor et winding is ener 'zed,

means actuated by the handle for closing the motor current exceeds a. predetermined starting contacts and for storing energy value, and means controlled b the armature 10 tending to close the running contacts, a togwhen opening to release t e restraining gle restraining the energy-storing means, means, whereby the running contacts may 5 an electromagnet having its winding conclose.

trolled by the motor current, an armature Signed at Cleveland, Ohio, this 21st day for the electromagnet biased to open posi of July, 1922. tion but prevented from opening when the- HARRY F. STRATTON. 

